[cells-gtk-devel] cells-gtk drawing-area widget

[Martin Flack]

Hi all,

I'm writing some stock equities charting software in Common Lisp for my
own amusement and to learn the language. I'd like to start by porting
over a simple program I had in Perl to draw daily price bars. I used Tk
in Perl so I was planning to use LTK but cells-gtk caught my eye and
looks interesting.

I noticed the drawing.lisp is commented out in the asdf file - is anyone
actively using this widget in their code? I uncommented it and got it to
compile on SBCL.

Secondly, I can't seem to get the widget to come up. I lifted some
example code from Google, but something's wrong. What I'm trying is
below - what happens is the program runs fine but there is no graphic
element, just the text label and entry box.

Tk does offer a canvas widget which might be helpful to my application,
but I'm thinking that since the objects I'd want to handle will be
conceptually higher than lines, rectangles, etc. that I could program my
own canvas-type abstraction anyway.

Any comments would be appreciated. Thanks! ;-)

Martin


(require :cells)
(require :cells-gtk)

(defpackage hello-world
  (:use :cl :cells :cells-gtk)
  (:export :main))

(in-package :hello-world)

(defmodel hello-world (gtk-app)
  ()
  (:default-initargs
    :title "Test"
    :position :center
    :width 650 :height 550
    :kids (list
	   (mk-notebook
	    :tab-labels (list "Tab 1")
	    :kids (list
		   (mk-vbox
		    :kids (list
(mk-label :text (c? (md-value (fm^ :mytext))))
(mk-entry :md-name :mytext :auto-aupdate t :init "Hello, World.")
(mk-drawing-area :md-name :drawing-area :width 100 :height 100
 :draw-fn
   #'(lambda (self)
       (with-pixmap (p "demo" :widget self :width 100 :height 100)
         (with-gc (p :fg "red")
           (draw-line p 0 0 100 100))
         (draw-text p "this is text" 10 70)
         (draw-rectangle p 10 10 30 30)
         (draw-rectangle p 1 1 97 97)
         (insert-pixmap p 0 0)
         p))))))))))

(defun main (&optional dbg)
  (cells-gtk-init)
  (start-app 'hello-world :debug dbg))